Abstract: Seismic data acquisition system, method, and connecting part configured to connect a lead-in to a streamer. The connecting part includes a single body extending along a longitudinal axis (X) between the lead-in and the streamer; the single body has a first end configured to connect to the lead-in through a first connection device and the body also has a second end configured to connect to the streamer through a second connection device; at least a link connecting the first end to the second end and configured to receive a tension that appears in the single body; a cable extending through the single body and configured to provide data communications; and plural modules provided on the single body. The single body is configured to wound-up on a spool.